This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A138347 #20 Nov 19 2021 17:38:11 %S A138347 1,2,3,6,10,21,39,86,182,440,1074,2941,8424,26720,90883,340253, %T A138347 1384567,6186907,30219769,161763233,946742190,6054606722,42229136988, %U A138347 320741332093,2648348712904 %N A138347 Number of squarefree bipartite graphs on n vertices. %H A138347 CombOS - Combinatorial Object Server, <a href="http://combos.org/nauty">Generate graphs</a> %H A138347 B. D. McKay, <a href="http://users.cecs.anu.edu.au/~bdm/publications.html">Isomorph-free exhaustive generation</a>, J Algorithms, 26 (1998) 306-324. %Y A138347 Cf. A006786, A300749. %K A138347 nonn %O A138347 1,2 %A A138347 _Vladeta Jovovic_, May 18 2008 %E A138347 More terms from _Brendan McKay_, Feb 04 2013 %E A138347 One more term from _Brendan McKay_, Mar 11 2018